Transcript for Exclusive look inside a nuclear-powered guided missile submarine
We are back now with that ABC news exclusive. "World news tonight" anchor David Muir taking us on a rare trip into the dime on a nuclear-powered Navy submarine that's now on a classified mission in the eastern mediterranean. David is here with us right now and, boy, what access you received. Yeah, you all were asking questions in the commercial break. This was extraordinarily rare to get access to a submarine of this kind, especially given the classified nature of the mission it is now on. What you're about to see, the tomahawk, the torpedoes, the nuclear reactor and the warning about who else is in the water right now. This morning, the "Uss Fordham" is somewhere in the eastern mediterranean on a highly classified mission. They call it the silent service for a reason. That's right. All those missions are some of the most highly classified we Reporter: A nuclear-powered U.S. Navy guided submarine. 160 on board. We are given rare access as we board the submarine. Rear admiral William Houston describes where we are standing, just above the tomahawk missiles. This can lift up at any time. 24 could lift up at any time on order if we wanted to launch the tomahawk missiles. How many are we sort of standing on? Right now, seven. Reporter: They have more than 100 tomahawks at the ready and they are about to take us down into the submarine where we will spend the next 24 hours traveling with them. A maze of narrowal ways and hatches as we prepare to climb to the top of the sub, we wait for word. Control bridge send ABC to the bridge. Reporter: Up the ladder they tell you when it comes to your hands and feet make sure three out of four are touching at all times. We climb several floors to meet the captain and members of his crew waiting atop "The uss Florida" where we find they are on patrol. Back down inside the submarine captain Seth Burton takes us past the missile tubes holding the tomahawks. Inside this tube right here. Seven missiles. Seven tomahawk missiles. Reporter: We take note in between the curtains drawn where the sailors sleep. The sailors are actually sleeping. Right, right. Reporter: Inside the submarine control room they are about to deliver the order to descend. Subcommercial. Dive, dive. Reporter: The subscriber marine disappearing under the water's surface. 400 feet. Reporter: Descending 400, 500, more than 600 feet. 13 degree up angle. Reporter: Soon we are all leaning with no effort. They have to be ready to make these moves. There are others here too. Do you have company in the We do have plenty of company. The Russians are very active and we're active with them. Reporter: The U.S. Aware of the rugs are trying to send a message. The Russians have demonstrated their willingness to use missiles from submarines. They did it from the black sea into Syria and now they're in the mediterranean. They absolutely are and we're watching them very, very closely. Reporter: Are they watching I think they'd like to watch out. Reporter: In fact the Russians recently were showing their own underwater muscle in the sea. An infrared camera. Full no contact. Reporter: So we're alone. Nobody is there. Which is good. Reporter: We crawl through another hatch and snake our way to the nuclear reactor. We're basically traveling on this submarine with a nuclear reactor. Absolutely. We can operate more than 90 to 120 days submerged. Reporter: It is always ready for U.S. Special forces, for Navy S.E.A.L., their weapons already on board. We are about to climb to sea the small compartment attached to the top of the submarine where Navy S.E.A.L.S, U.S. Special forces would deploy right into the water. This is the dry deck shelter. In fact we're still about 200 feet beneath the surface of the mediterranean here in this room. This is where the Navy S.E.A.L.S would deploy and a Navy S.E.A.L. Delivery vehicle of some sort and, in fact, the only thing separating me from the intense pressure of the water is this black hatch and, in fact, if you listen, you can actually hear the water. And on board there is one more powerful weapon. The torpedo. As a captain you always want to be ready and -- This one here? Right. Reporter: They have eight of them on board the submarine "The uss Florida" now on that classified mission. Nobody knows where it is at in the mediterranean at any one time. Including now. Including now. You know, you saw that hatch leading to the nuclear reactor on board. Had submarine has been in the water for more than 30 years now at work. It's only been refueled once because of that nuclear reactor. Their missions can last up to 120 days, four months they spend underwater. They make their own oxygen once they're down below breaking the hydrogen from the oxygen using electricity. The only thing they run out of after a certain period of time is food. For that entire four months they don't surface at all. 2340, oftentimes if they're on a classified mission. What was it like down underneath. You don't feel it in your ears. It is pressurized but the quarters are quite small. I give these folks a lot of credit. They sleep in bunks about this tall and you climb up into them. I won't forget it. Bless them one and all. And missiles at that. Right in between the tomahawk missiles as they walk down the hallway is where they sleep. Thank you, David. And coming up, it's very superstitious.
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